[20:33:13] [Thread-10/ERROR] [Mekanism/Mekanism]: An error occured while connecting to URL 'https://dl.dropbox.com/u/90411166/Mod%20Versions/Mekanism.txt.'

Shows up in the logs while starting the server. I reckon you can easily replace the URL :)

what version of mek are you using?

Dropbox has had some strange instability issues over the past few months, and I'm pretty sure they're gonna be discontinuing their public links service fairly soon. I'm gonna move to directly host the donators and news files from my website fairly soon, that should fix the issues.